The active center concentration Cp

the rate constant Kp

and the activation energy of chain propagation Ep

etc. in the polymerization of propylene with complex-type TiCl2-(C2H5)2 A1C1 catalyst system were determined.The value obtained for Cp

Kp and E2 at 50℃ are 3.01 mol/mol Ti

6.27 1/mod

sec. and 5.10 Kcal/mol respectively.The kinetic parameters are compared with the data obtained from the conventional TiCl2. 0.33 AlCL

showing that the higher activity of the complex-type catalyst over the conventional catalyst is notonly due to the higher Cp value of the former

but to a greater extent

dut to the increase of the kp value.